Lost in the shuffle of health care debates and Syrian airstrikes, America’s most boisterous union recently released its 2016 financials. The Service Employees International Union (SEIU) — the catalyst of the Fight for $15 and a Union campaign — reveals exactly how union bosses spent member dues money last year.

Let’s go down the list, starting with the SEIU’s wage war. In 2016, the SEIU spent more than $19 million on Workers Organizing Committees (WOCs), public relations retainers, and legal fees to accelerate the Fight for $15 nationwide. The Fast Food Workers Committee, a WOC helping the SEIU run its campaign, received more than $3.6 million last year. BerlinRosen Public Affairs, a Democratic consulting firm, made off with more than $1.7 million, while the Mario Cuomo Campaign for Economic Justice secured $250,000 from the SEIU.

WOCs — SEIU-funded quasi-unions that organize protests and street theater — received the lion’s share of funding: $14.7 million in 2016. Since the campaign launched in 2012, the SEIU has spent at least $90 million on the Fight for $15 and a Union.

So SEIU membership has skyrocketed in recent years, right? Wrong. Despite deploying the Fight as a national recruitment tool, employees are leaving the union at the altar. Since 2011 — the year before the campaign began — the union has lost nearly 21,000 dues-paying members. You read that right: The union has spent tens of millions of dollars on its misguided minimum wage fight and lost thousands of members.

As Andy Stern, the former president of the SEIU, observes: “The union can’t just keep transferring revenue it makes from bargaining contracts to pay for its social justice work because collective bargaining is shrinking.” In the words of pro-union columnist Harold Meyerson: “[T]here’s a limit to how much unions can win politically if they continue to shrink.” And they’re shrinking fast.

It doesn’t help that the SEIU wastes money on frivolous expenses unrelated to collective bargaining. According to the union’s 2016 filings, the SEIU dropped more than $285,000 in “support for political activities” on Las Vegas’ Stratosphere Hotel. On another occasion, the union spent roughly $40,000 on “staff meetings and training” at the premier St. Regis in Washington, D.C., where hotel rooms go for $600 a night.

Then there’s the $33,000 night of catering in Philadelphia, only to be outdone by the $48,000 spent on a Pennsylvania limousine company. Another $10,000 was spent in a single night at a Capitol Hill bar.

Who knew that collective bargaining could be so stressful?

When union bosses aren’t grabbing a few cocktails, they’re spending millions of dollars on political advocacy. Like other unions, the SEIU complements its direct support for Democratic candidates with thinly veiled funding of Democrat-aligned special-interest groups. (While union members must consent to the former, union bosses need no permission for the latter.)

There’s the $155,000 to the left-wing Americans United for Change and another $253,000 to the Center for Popular Democracy, a liberal advocacy group with a “racial and economic justice agenda.” The Economic Policy Institute — a left-wing think tank — received another $150,000, even though 43 percent of union household members vote Republican. (In SEIU President Mary Kay Henry’s words: “64 percent of our public members identify as conservative.”)

In 2016, Ms. Henry earned more than $262,000 in total compensation, all the while complaining that “our economy and democracy have been taken over by the wealthiest 1 percent.” She is joined by dozens of other SEIU six-figure earners, many of whom make more than $200,000 a year while criticizing corporate “fat cats.” According to a Rasmussen poll conducted before the election, only 20 percent of Americans see labor leaders as “do[ing] a good job representing union members.” Even among current or former union members, only 25 percent have a favorable view of union leadership. Can you blame the millions of union members who supported Donald Trump last November?

President Trump personified change. With that shift comes a chance to seize power from union elites and return control of millions in dues money to the members.

• Richard Berman is the president of Berman and Company, a public affairs firm in Washington, D.C.